The atomic numbers for both the stable and radioactive forms of nitrogen have the atomic number 7.
Stable Mass: 14
Radioactive Mass: 16
I would say B ? Should be correct
<span>a strong downward current of air from a cumulonimbus cloud, usually associated with intense rain or a thunderstorm.</span>
Facilitated diffusion of substances crossing the cell (plasma) membrane takes place with the help of proteins such as channel proteins and carrier proteins.